Analysis of four-wave mixing in semiconductor optical amplifiers for optical frequency conversion and optical phase conjugation

We report a complete large-signal dynamic model of wavelength converter and optical phase conjugator based on four-wave mixing (FWM) in semiconductor optical amplifier (SOA). In SOA model using time developed transfer matrix method (TMM), we take into account of not only forward traveling waves but also backward traveling waves and include longitudinal variation of carrier -induced refractive index, alpha-parameter, gain, carrier density, photon d ensity, reflection, and ASE noise at each small section. Therefore, we can accurately estimate optical pulse patterns, frequency chirping, and extinct ion ratio of conjugate signal, which affect transmission performance. In or der to investigate the effects of frequency chirping on transmission perfor mance, eye-opening penalty (EOP) has been calculated.